I am towing a 28' trailer that has a dry weight of 6k and with the options and loaded modestly for a week of camping comes in at 8100 on the scale. The F150 Max Tow with HD Payload has towed this well. I am fine on payload (2,200) but with a tongue weight of 1,100 I am just about maxing out the receiver hitch which is rated at 1,150. The HD Payload is only available with the longer wheelbase which gives you a 6 1/2 foot bed with the crew cab.
I put 10k miles a year on the truck, with about 1k towing or less.
The EcoBoost engine coupled with the 6 speed transmission and a good integrated trailer brake controller perform very well. Happy with the truck, but consider this to be the most I would want to tow with it as I like to stay within the specs. I have not had this rig out in strong side winds yet, but that is one case where the extra size of the SuperDuty would probably be nice. The HD brings more capability, but it is not an F250.
Given that your dry weight is higher yet you may well be at 9k loaded with a tongue weight in excess of the receiver rating. That will bump you into F250 country.
Any chance you can put your trailer on a scale and nail down your actual trailer and tongue weights?
Good luck,
Stu